Is My Dog Sick? How Can I Tell?

Published by
min read

Find food that fits your pet’s needs

Find a dog food that fits your pet’s needs

Find a cat food that fits your pet’s needs

If you're a new dog parent and your dog is acting weird, you may be wondering, "what's wrong with my dog?" Even if you suspect something is wrong, you may not know how to tell if they are actually sick, what a sick dog looks or acts like, and why your pup's strange behaviour may keep you up at night. And if your dog is actually sick and you don't notice the signs (of they're just good at hiding it), you may feel guilty and sad that you didn't know your dog was hurting.

While some symptoms of sickness, such as vomiting or diarrhoea, can be obvious, many sickness behaviours in dogs are hard to pick up on if you don't know what to look for. Here are a few situations and signs that can help you figure out if your dog could be sick, and when you should consider contacting your veterinarian.

Sign #1: They're Not Eating

Most dogs will rarely miss a meal or special treat — especially when you set it in front of them. If your dog turns their nose up at their breakfast or dinner when they're normally gobbling it down, it's time to pay attention. Many things can cause a dog to stop eating. Nausea, tooth pain, anxiety, hormonal disorders, viral infections and gut pain are just a few of many things that can cause a dog to stop eating.

Schedule an appointment with your veterinarian if your dog doesn't eat for more than a day or misses more than two meals.

Sigh #2: They're Just Lying Around

Birds eye view of small fluffy dog laying on oak hardwood floor with toys scattered around them.

If you notice that your dog is sleeping more, dragging behind on walks, uninterested in play or not playing as much as they used to, then something might be wrong. Sometimes, it's just too hot outside to play and exercise. When the temperatures rise, dogs are naturally a little more lazy. On the other hand, if it's not hot, then this behaviour indicates that something more may be at play.

There are many things that can cause loss of energy in a dog. Any kind of infection, whether it be viral, bacteria or fungal, can cause loss of energy. Heart disease or breathing problems of any kind can make a dog feel tired. Hormonal disorders, such as low thyroid, can cause increased lethargy and sleeping. Obesity can cause a dog to sleep more because it is exhausting to get around. Obesity can also lead to things like degenerative joint disease making it more painful for your dog to get around. This then creates a cycle because your dog cannot easily exercise to lose weight. If your veterinarian suggests that your dog is obese, it is important to take their advice and work with them on a weight loss plan. Cancer, liver disease, kidney disease and neurological conditions such as seizures or canine cognitive dysfunction (otherwise known as doggie Alzheimer's disease) can also all make a dog act tired.

If your dog is getting up there in years, you might also think that they are moving less due to old age. While it is true that dogs slow down as they get older, it doesn't mean they should stop moving altogether. Senior dogs (those that are seven years and older) are still very capable of getting around and exercising, so if your older pup doesn't seem to play like they used to, it's probably worth a call to the veterinarian and have them checked out more frequently than their annual vet visit, just to rule out any possible ailments. As your dog ages, your veterinarian will likely want to perform additional tests to ensure your pup stays in tip-top shape.

Pain can also masquerade as loss of energy. Gastrointestinal problems that cause a painful belly can make a dog act lethargic, and if a dog is in pain from arthritic joint disease, the pain may just manifest as sleeping more. The bottom line is that increased sleeping or laziness can definitely signal a problem. If it lasts for more than a day, call your vet. It's always better to be proactive and call your vet than wonder if your dog is sick for days.

Sign #3: They're Drinking a Lot of Water

If you notice that your dog is constantly draining the water bowl, asking to be let out more often or having accidents in the house, then your dog might be sick. Drinking a lot from excessive thirst is called polydipsia. Some of the common causes of polydipsia include hormonal conditions such as diabetes mellitus or hyperadrenocorticism, as well as kidney disease also known as Cushing's disease, says Merck Veterinary Manual. Liver disease and severe uterine infections can also cause a dog to drink more. If you notice that your dog is drinking more than normal, it's not hot outside and the behavior lasts more than a day or two, call your vet and make an appointment.

Sign #4: You Can Feel Their Ribs

Weight loss can be hard to detect, especially if your dog has long hair. Sometimes, pet parents don't know that their dog has lost weight until the dog is weighed by their vet. Dogs lose weight for one of two reasons: either they aren't eating or absorbing enough nutrients, or they are burning too many calories. Cancer, diabetes, liver disease and kidney disease as well as other diseases all cause weight loss. If you notice that your dog's ribs or hips are sticking out, then your dog could be sick. Call your veterinarian.

The best way to know if something is wrong is to know how your dog behaves normally, including their eating, drinking, urinating and defecating patterns, as well as what their normal stool looks like and what their normal energy level is. When petting your dog, feel all over and look for anything out of the ordinary, like rashes or lumps and bumps. You can also tell whether your dog is at a normal weight with an easy test you do at home called the hand test.

You know your dog better than anyone, and if something makes you wonder if there is something wrong with them or that they are sick trust your gut and enlist the help of your veterinarian.

Contributor Bio

Dr. Sarah Wooten

Dr. Sarah Wooten


A 2002 graduate of UC Davis School of Veterinary Medicine, Dr. Sarah Wooten is a well-known international speaker in the veterinary and animal health care spaces. She has 10 years experience in public speaking and media work, and writes for a large number of online and print animal health publications. Dr. Wooten has spoken in the veterinary education space for 5 years, and speaks on leadership, client communication, and personal development. Dr. Wooten is also a certified veterinary journalist, a member of the AVMA, and has 16 years experience in small animal veterinary practice. In addition to being a speaker, author, veterinarian, and co-creator of the wildly popular card game 'Vets Against Insanity', she co-owns Elevated Eateries Restaurant group in Greeley with her husband of 21 years, and together they are raising 3 slightly feral mini-humans. When it is time to play, she can be found skiing in Colorado, diving with sharks in the Caribbean, or training kenpo karate in her local dojo. Go big...or go home. To learn more, visit


Related Articles

  • Watching your puppy's weight

    Puppy and pet dieting, cat nutrition and dog nutrition information from Hill's Pet
  • Why Dogs Throw Up After Eating

    Learn what can cause your dog to throw up recent food, such as eating too fast or changing to a new food, as well as how you can prevent it from happening.
  • Does dry nose mean sick dog?

    A dog's nose can be an indicator of health. Know how to best care for your dog if their nose is dry, cracked, warm, red, flaky, or has nasal discharge.
  • Pregnancy in dogs

    Learn the signs that your dog might be pregnant, as well as what you can do to provide her with the best care and prepare for the new litter of puppies.

Related products